JP5651462B2 - Method of recovering valuable material from lithium ion secondary battery and recovered material containing valuable material - Google Patents

Description

  The present invention relates to a lithium ion secondary battery capable of recovering valuable materials such as cobalt from defective lithium ion secondary batteries generated during the manufacturing process, lithium ion secondary batteries that are discarded with the use of equipment and battery life, and the like. The present invention relates to a method for recovering valuable materials from secondary batteries, and a recovered material containing valuable materials obtained by the recovery method.

Lithium-ion secondary batteries are lighter, higher-capacity, and higher-electromotive force secondary batteries than conventional lead-acid batteries and nickel-cadmium secondary batteries, and are used as secondary batteries for personal computers, electric vehicles, portable devices, etc. Has been. Valuables such as cobalt and nickel are used for the positive electrode of the lithium ion secondary battery as lithium cobaltate (LiCoO ₂ ), a ternary positive electrode material (LiNi _x Co _y Mn _z O _{2 (x + y + z)} ), and the like. Yes.

Lithium ion secondary batteries are expected to continue to be used in the future, so defective products generated during the manufacturing process, used equipment, and valuable resources such as cobalt from lithium ion secondary batteries that are discarded along with battery life. It is desired from the viewpoint of resource recycling to collect the goods.
When recovering the valuable material from the lithium ion secondary battery, it is important to separate and recover various metals used from the viewpoint of increasing the value of the recovered material. In particular, it is very important to separate and recover the valuable material from iron or the like in terms of increasing the value of the recovered material containing the valuable material.

As a method for recovering valuable materials, primary lithium secondary batteries are first roasted at a temperature of 350 ° C. or higher, then crushed by a shearing type crusher, and then crushed material is sieved. Subsequent roasting, treatment with acid, pH is adjusted to 4 to 5.5 while blowing an oxidizing gas into the treatment liquid, filtration is performed, alkali is added to the filtrate, and filtration is performed to collect a precipitate. Has been proposed (see Patent Document 1).
Also proposed is a cobalt recovery method in which used lithium secondary batteries are roasted at a temperature of 350 ° C or higher, then crushed by a shearing crusher, the crushed material is sieved, and the screen is magnetically sorted. (See Patent Document 2).
However, with these proposed technologies, in the crushing process, valuable materials such as cobalt can be sufficiently separated from other metals such as iron used in the battery case (housing) in the subsequent screening process. Since it has not been crushed to a certain state, valuable materials such as cobalt remain on the sieve after the sieve selection. As a result, there is a problem that the recovery rate of valuable materials in the recovered material obtained under the sieve is lowered. In addition, since iron etc. are contained on the sieve, it is not economical to collect valuable materials from the sieve because more processes are required. In addition, when a shearing type crusher is used, iron with small particles is generated and mixed into the recovered material under the sieve. Since both iron and cobalt are magnetized, there is a problem that when cobalt is magnetically sorted after sieve sorting, iron is also collected at the same time, and iron is mixed as an impurity in the collected material.
In addition, there is a problem in that there is a risk of explosion due to generation of dust mainly composed of carbon of the negative electrode when crushing or sieving with a dry method.

  In addition, it has been proposed to perform separation with a ball mill using alcohol after disassembling a lithium ion secondary battery without roasting (see Patent Document 3). However, with this proposed technology, the problem that several separation steps are required, and iron as the metal of the battery case (housing) is crushed and mixed with valuable materials contained in the electrode, and the recovered material is collected. There is a problem that iron is often mixed as an impurity.

  Therefore, valuable materials such as cobalt can be recovered from lithium-ion secondary batteries at a high recovery rate, and the amount of impurities such as iron contained in the recovered materials containing the valuable materials is small, and the recovery of valuable materials is simpler. Currently, there is a need for a method and a recovered material containing valuable materials obtained by the recovery method.

JP-A-7-207349 JP 7-245126 A JP 2007-122885 A

  An object of the present invention is to solve the above-described problems and achieve the following objects. That is, the present invention can recover valuable materials such as cobalt from a lithium ion secondary battery at a high recovery rate, and the amount of impurities such as iron contained in the recovered material containing valuable materials is small, and the process is simple. It is an object of the present invention to provide a method for recovering a valuable material and a recovered material containing the valuable material obtained by the recovery method.

Means for solving the problems are as follows. That is,
<1> A roasting step of roasting a lithium ion secondary battery containing a valuable material in a metal battery case to obtain a roasted product,
A separation step of stirring the roasted product together with a liquid to separate the content containing the valuable material from the inside of the metal battery case;
Screening the contents separated from the separation step and the metal battery case to obtain a recovered material containing the valuable material, and including a valuable step from the lithium ion secondary battery. This is a method for collecting goods.
<2> The method for recovering a valuable material from a lithium ion secondary battery according to <1>, wherein the valuable material is cobalt.
<3> The valuable from the lithium ion secondary battery according to any one of <1> to <2>, wherein the separation step is performed in any of a ball mill, a rod mill, a media-free mill, and a rotary washing machine. This is a method for collecting goods.
<4> Recovery of valuable materials from the lithium ion secondary battery according to any one of <1> to <3>, wherein the amount of liquid used in the separation step is 0.5 kg to 100 kg with respect to 1 kg of the roasted product. Is the method.
<5> The method for recovering a valuable material from a lithium ion secondary battery according to any one of <1> to <4>, wherein the sorting step is performed by sieving.
<6> The method for recovering a valuable material from a lithium ion secondary battery according to <5>, wherein the particle size of the recovered material obtained by sieving is 1 mm or less.
<7> A recovered material containing a valuable material obtained by the method for recovering a valuable material from a lithium ion secondary battery according to any one of <1> to <6>.

  According to the present invention, the conventional problems can be solved, valuable materials such as cobalt can be recovered from the lithium ion secondary battery at a high recovery rate, and impurities such as iron to the recovered material containing the valuable materials can be recovered. Therefore, it is possible to provide a method for recovering valuable materials with a small amount of contamination and a simple process, and a recovered material containing valuable materials obtained by the recovery method.

1 is a photograph of a metal battery case after the separation step in Example 1. FIG. FIG. 2 is a photograph of the baked product after crushing in Comparative Example 1. FIG. 3 is a photograph of a metal battery case after the separation step in Comparative Example 2 and a mixture of contents.

(Recovery method of valuable materials from lithium ion secondary batteries and recovered materials containing valuable materials)
The method for recovering valuable materials from the lithium ion secondary battery of the present invention includes at least a roasting step, a separation step, and a sorting step in this order, and further includes other steps as necessary.
The recovered material containing the valuable material of the present invention is obtained by the method for recovering the valuable material from the lithium ion secondary battery of the present invention.

<Roasting process>
The roasting step is not particularly limited as long as it is a step of roasting a lithium ion secondary battery to obtain a roasted product, and can be appropriately selected according to the purpose.

-Lithium ion secondary battery-
The lithium ion secondary battery is not particularly limited as long as it is a lithium ion secondary battery including a metal battery case and a valuable material in the metal battery case, and is appropriately selected according to the purpose. For example, a defective lithium ion secondary battery generated in the manufacturing process of a lithium ion secondary battery, a lithium ion secondary battery that is discarded due to a failure of the device used, a life of the device used, etc. And used lithium ion secondary batteries.

  Examples of the lithium ion secondary battery include a positive electrode, a negative electrode, a separator, an electrolytic solution containing an electrolyte and an organic solvent, and a metal battery containing the positive electrode, the negative electrode, the separator, and the electrolytic solution. And a lithium ion secondary battery including a case.

  There is no restriction | limiting in particular as said metal battery case, According to the objective, it can select suitably, For example, an iron battery case is mentioned. The iron battery case may contain a metal other than iron, such as nickel, or may be an alloy.

There is no restriction | limiting in particular as said positive electrode, According to the objective, it can select suitably, For example, the positive electrode provided with the electrical power collector which consists of aluminum foil, and the positive electrode material provided on the said electrical power collector is mentioned. It is done.
The positive electrode material is not particularly limited as long as it contains valuable materials, and can be appropriately selected according to the purpose.For example, the positive electrode material includes at least a composite oxide containing valuable materials, and if necessary, a conductive agent and And a positive electrode material containing a binder resin.
Examples of the valuable materials include cobalt and nickel.
Examples of the composite oxide include lithium cobaltate (LiCoO ₂ ), lithium cobalt nickelate (LiCo _1/2 Ni _1/2 O ₂ ), and LiNi _x Co _y Mn _z O _{2 (x + y + z)} .

  There is no restriction | limiting in particular as a shape of the said lithium ion secondary battery, According to the objective, it can select suitably, For example, a cylindrical shape, a button shape, a coin shape, a square shape, a flat shape etc. are mentioned.

-Roasting-
By performing the roasting, the current collector (for example, aluminum foil) to which the positive electrode material containing the valuable material is attached is easily melted and separated from the positive electrode material. Further, the organic matter in the contents inside the lithium ion secondary battery, such as an electrolyte, burns, so that the pressure (internal pressure) inside the lithium ion secondary battery increases, and the safety valve of the metal battery case As a result, the contents containing the valuables are easily separated from the metal battery case in the separation step. Therefore, the content containing the valuables can be easily separated from the inside of the metallic battery case by stirring in the separation step which is the next step. Further, since the positive electrode material can be easily made fine after being separated from the current collector, the positive electrode material containing valuable materials and iron such as the current collector and the battery case are highly sorted by a sieve or the like. become able to.

There is no restriction | limiting in particular as a roasting temperature of the said roasting, Although it can select suitably according to the objective, 400 degreeC or more is preferable and 650 to 800 degreeC is more preferable. When the roasting temperature is less than 400 ° C., the current collector hardly melts, and as a result, the recovery rate of the valuables may be lowered. When the roasting temperature exceeds 800 ° C., it may be impossible to recover a desired valuable material by melting the battery case constituent material.
Here, the roasting temperature refers to the temperature of the lithium ion secondary battery during roasting. The roasting temperature can be measured by inserting a thermometer such as a couple or thermistor into the lithium ion secondary battery being roasted.

  The roasting time for the roasting is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1 minute to 5 hours, more preferably 1 minute to 2 hours, and 1 minute to 1 hour. Particularly preferred. The roasting time may be any roasting time for the current collector and the positive electrode material to reach a desired temperature, and the holding time may be shorter than that time. When the roasting time is within the particularly preferable range, it is advantageous in terms of cost for roasting.

  There is no restriction | limiting in particular as said roasting method, According to the objective, it can select suitably, For example, performing using a roasting furnace is mentioned. Examples of the roasting furnace include a batch kiln such as a rotary kiln, a fluidized bed furnace, a tunnel furnace, and a muffle furnace, a cupola, and a stalker furnace.

The roasting atmosphere is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include an air atmosphere, an oxidizing atmosphere, an inert atmosphere, and a reducing atmosphere. In addition, it is preferable to aerate during roasting.
Here, the air atmosphere (air atmosphere) means an atmosphere using air (air) in which oxygen is 21% and nitrogen is 78%.
The oxidizing atmosphere means an atmosphere containing 1% by mass to 21% by mass of oxygen in the inert atmosphere, and an atmosphere containing 1% by mass to 5% by mass of oxygen is preferable.
The inert atmosphere means an atmosphere made of an inert gas such as nitrogen or argon.
Examples of the reducing atmosphere include an atmosphere containing CO, H ₂ , H ₂ S, SO _{2 and the} like in the inert atmosphere.
Among these, an air atmosphere (air atmosphere) is preferable in terms of easy control of the furnace atmosphere.

<Separation process>
The separation step is not particularly limited as long as it is a step of stirring the roasted product together with a liquid to separate the content containing the valuable material from the inside of the metal battery case, and is appropriately selected depending on the purpose. can do.
Since most of the contents inside the metal case of the lithium ion secondary battery are fine and brittle due to the roasting step, the roasted product is stirred with a liquid in the separation step. Thus, the contents containing the valuables can be easily separated from the metal battery case.
By the separation step, for example, the content containing the valuable material is extracted from the inside of the metal battery case.

-Agitation-
There is no restriction | limiting in particular as said stirring, According to the objective, it can select suitably.
Here, the agitation is performed so as not to crush or crush the metal battery case. This is because if the metal battery case is crushed or pulverized, it becomes difficult to separate and collect the metal such as iron as the battery case material and the valuables. In the agitation, there is no problem that the metal battery case is slightly recessed.
Further, in the roasting step, even if the safety valve of the metal battery case is not detached, the safety valve can be removed by the impact during the stirring.

The stirring method is not particularly limited and may be appropriately selected depending on the intended purpose. However, the stirring method is preferably any of a ball mill, a rod mill, a media-free mill, and a rotary washing machine.
Here, when stirring with a mill, if a medium is used, the metal battery case is crushed or crushed, or the metal battery case is deformed into a plate shape. Is not used. In the case of using a medium, it is preferable to carry out the conditions under such a condition that the metal battery case is not crushed or crushed and is not deformed into a plate shape.

There is no restriction | limiting in particular as said liquid, According to the objective, it can select suitably, For example, water, an organic solvent, etc. are mentioned.
Examples of the water include acidic water, neutral water, and alkaline water.
Examples of the organic solvent include alcohol solvents, glycol solvents, glycol ether solvents, and the like. Examples of the alcohol solvent include methanol, ethanol, propanol, isopropanol, butanol, 2-butanol, tert-butanol, and the like. Examples of the glycol solvent include ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol. Examples of the glycol ether solvent include ethylene glycol methyl ether, propylene glycol methyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, and dipropylene glycol. Propyl ether, Dipropylene glycol butyl ether, Triethylene glycol methyl ether, Triethylene glycol ethyl ether, Triethylene glycol propyl ether, Triethylene glycol butyl ether, Tripropylene glycol methyl ether, Tripropylene glycol ethyl ether, Tripropylene group Call propyl ether, tripropylene glycol butyl ether.

  There is no restriction | limiting in particular as the usage-amount of the said liquid, Although it can select suitably according to the objective, 0.5 kg-100 kg are preferable with respect to 1 kg of roasted products, and 1 kg-5 kg are more preferable. When the amount used is less than 0.5 kg, the liquid such as water is not sufficiently distributed, so that the metal battery case is well separated from the contents containing the valuables. If it exceeds 100 kg, disposal of the liquid may become difficult after solid-liquid separation.

  There is no restriction | limiting in particular as stirring time, Although it can select suitably according to the objective, 1 minute-5 hours are preferable, 5 minutes-3 hours are more preferable, and 10 minutes-2 hours are especially preferable. If the stirring time is less than 1 minute, separation may be insufficient and the recovery rate of the valuable material may be reduced. If the stirring time exceeds 5 hours, separation may be difficult during the sorting step due to over-pulverization. In addition, the metal battery case may be scraped by friction, and the concentration of impurities in the recovered material may increase.

  Performing the separation step together with the liquid, that is, performing it in a wet manner has an advantage that dust explosion due to carbon contained in the roasted product can be prevented. Moreover, there is an advantage that the contents containing the valuables can be efficiently separated from the inside of the metal battery case.

  Here, FIG. 1 shows a photograph of the metal battery case after the separation step. The metal battery case is not crushed and crushed although the safety valve is removed and there are some dents. Moreover, the contents inside the metal battery case are separated by the separation step.

<Selection process>
The sorting step is not particularly limited as long as it is a step of sorting the contents separated in the separation step and the metal battery case and obtaining a recovered material containing the valuable material. It can be selected as appropriate, but it is preferable to carry out by sieving because the apparatus is simple and the operation is simple.

-Sieving-
There is no restriction | limiting in particular as said sieving, According to the objective, it can select suitably, For example, it can carry out using a vibration sieve, a multistage vibration sieve, a cyclone, the standard sieve of JISZ8801, etc.
There is no restriction | limiting in particular as opening of the mesh of a sieve, Although it can select suitably according to the objective, 0.025 mm-2 mm are preferable, 0.025 mm-1.5 mm are more preferable, 0.075 mm- 1 mm is particularly preferable. When the mesh opening is less than 0.025 mm, the recovery rate of the valuables under the sieve may be reduced. When the mesh size exceeds 2 mm, iron scraps and the like are mixed under the sieve and further sorted. A process may be required. When the mesh opening is within the particularly preferable range, it is advantageous in that the recovery rate of the valuable material is improved.

  The sieving may be dry or wet. Among these, being wet is preferable in that the contents obtained in the separation step can be sifted without being separated from the liquid, so that the process can be simplified and dust can be prevented. .

On the sieve after the sieving, iron, aluminum and the like are mainly contained as a battery case and an aluminum foil, and the positive electrode material is mainly contained under the sieve.
The sieving is usually performed while shaking the sieve, in other words, applying vibration to the sieve. For example, valuable material (for example, cobalt) remains inside the battery case, or valuable material (for example, cobalt) Even if (cobalt) is encased, valuable materials (for example, cobalt) can be separated from the battery case and aluminum foil by vibration, so that the positive electrode material finely pulverized by the pulverization step can be efficiently screened. Selected.

In the sieving, the sieving may be further sieved.
Here, in the sieving selection step, when further sieving the sieving, the sieving on the first sieving is referred to as the first sieving, and the sieving is referred to as the first sieving, The top of the sieve when the first sieve is further sieved is called the second sieve, and the sieve is called the second sieve.
By further sieving the first sieving material, the carbon that is the material of the negative electrode is moved under the second sieving material, and the recovered material containing the valuable material remaining on the second sieving material is used. The carbon can be sorted out.
In the case of further sieving the first sieve, a multistage sieve can be used in the sieve sorting step. In addition, the first sieve and the second sieve can be sieved again.
There is no restriction | limiting in particular as an opening of the sieve screen at the time of further sieving the said 1st sieve bottom, Although it can select suitably according to the objective, 0.0075 mm-0.3 mm are preferable. 0.025 mm to 0.15 mm is more preferable, and 0.025 mm to 0.075 mm is particularly preferable. If the mesh opening is less than 0.0075 mm, the particle size may be too small to make sorting difficult. If it exceeds 0.3 mm, the recovery rate of the valuable material may be reduced. . When the mesh opening is within the particularly preferred range, it is advantageous in that the amount of the valuable material lost when the sieve is removed can be reduced as much as possible.

  There is no restriction | limiting in particular as a particle size of the collection thing of the said sieving obtained by the said sieving (the said 1st sieving), Although it can select suitably according to the objective, It is 1 mm or less, Is preferable from the viewpoint of a high recovery rate and a small amount of other impurities. Examples of the method for setting the particle size to 1 mm include sieving with a sieve having an opening of 1 mm.

  The method for recovering valuable materials from the lithium ion secondary battery does not require a secondary roasting step or a magnetic force sorting step after the sorting step, and the process is simple and cobalt and the like have a high recovery rate. It is possible to collect valuables.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1
A used lithium ion secondary battery for a personal computer was used as the lithium ion secondary battery.
-Roasting process-
A lithium ion secondary battery was placed in a muffle furnace (FJ-41, manufactured by Yamato Scientific Co., Ltd.), the roasting temperature was set to 800 ° C., and the temperature was increased to 800 ° C. at a temperature increase rate of 10 ° C./min. After reaching the temperature, it was baked for 1 hour to obtain a baked product. The atmosphere in the furnace was an air atmosphere.
-Separation process-
8 kg of the roasted product and 30 L of water obtained by the roasting step are put into a ball mill (volume 220 L) without media, stirred for 2.5 hours at a rotation speed of 50 rpm, and made of metal of the lithium ion secondary battery. The contents containing valuables contained in the metal battery case were extracted from the battery case.
-Sorting process-
The coarse particles in water separated in the separation step and the metal battery case in water were sieved using a sieve having a mesh opening of 1.00 mm.

<Evaluation>
After sieving, the upper and lower sieves were dried to remove moisture.
The mass on the sieve after drying and the mass under the sieve were measured, and the mass ratio on the sieve relative to the battery and the mass ratio under the sieve were determined.
In addition, the dried sieve and the sieve (recovered material) are dissolved in aqua regia by heating, and analyzed with a high-frequency inductively coupled plasma emission spectrometer (iCaP6300, manufactured by Thermo Fisher Scientific) to recover cobalt. Rate, the mixing rate of iron as an impurity, the metal content on the sieve, and the metal content under the sieve.
The results are shown in Table 1.

(Comparative Example 1)
In Example 1, instead of the separation step, a good cutter (UG-102-10-240, manufactured by Ujiie Seisakusho, blade width 10 mm), which is a shear type crusher, was used, except that 8 kg of the baked product was crushed for 10 seconds. In the same manner as in Example 1, valuable materials were collected and evaluated. The results are shown in Table 1. In addition, since crushing was performed by a dry type, drying after sieving was not performed.

(Comparative Example 2)
In Example 1, valuable materials were collected and evaluated in the same manner as in Example 1 except that 180 kg of iron media (iron balls having a diameter of 30 mm to 70 mm) was placed in a ball mill. The results are shown in Table 1.

  In Table 1, the cobalt (Co) recovery rate is the recovery rate when the cobalt contained in the lithium ion secondary batteries used in Examples and Comparative Examples is 100%. The iron mixing rate is the mixing rate when the total amount of iron before passing through the sieve is 100%. The metal content on the sieve is the content of cobalt and iron relative to the total quantity on the sieve. The metal content under the sieve is the content of cobalt and iron with respect to the total quantity under the sieve.

As shown in Table 1, the battery case made of iron was pulverized in Comparative Example 1 and Comparative Example 2, and both were mixed with the recovered material under the sieve that passed through an opening of 1.00 mm. 10.3% of the total amount of iron before passing was 100%, and in Comparative Example 2, 28.8% of iron passed through a sieve having an aperture of 1.00 mm. This resulted in contamination as an impurity in the recovered material containing valuable materials such as cobalt. Both iron and cobalt are magnetic deposits, and when magnetic separation is performed when cobalt is recovered, both iron and cobalt are magnetically recovered and separation becomes difficult.
On the other hand, in Example 1, the iron contamination rate in the recovered material containing valuables was very low at 7.0%, which was excellent.
Moreover, from the comparison of the mass on the sieve and under the sieve, it can be seen that in Comparative Example 1, the proportion on the sieve is higher than that in Example 1, and cobalt remains on the sieve. Moreover, in the comparative example 2, compared with Example 1, the ratio under sieving is high, and it turns out that the crushed material with a fine particle size is increasing by crushing too much.
From these results, in Example 1, cobalt that is the content of the lithium ion secondary battery can be recovered without being excessively pulverized in a state where iron that is mainly an impurity is small.

  FIG. 1 shows a photograph of the metal battery case after the separation step in Example 1. FIG. 2 shows a photograph of the baked product after crushing in Comparative Example 1. Moreover, the photograph of the metal battery case after the separation process in Comparative Example 2 and the mixture of the contents is shown in FIG. In Example 1, although the metal battery case had some dents, it was not crushed or crushed, and the contents were extracted from the metal battery case. On the other hand, in Comparative Example 1 and Comparative Example 2, the metal battery case was crushed or pulverized to become a fine crushed material or pulverized material.

  The method for recovering a valuable material from a lithium ion secondary battery according to the present invention can recover a valuable material such as cobalt from a lithium ion secondary battery at a high recovery rate, and the amount of iron mixed in the recovered material containing the valuable material Since the process is simple and the process is simple, it can be suitably used for recovering valuable materials from lithium ion secondary batteries.

Claims (7)

A roasting step of roasting a lithium ion secondary battery containing valuables in a metal battery case to obtain a roasted product;
A separation step of separating the contents of the roasting was stirred so as not to crush or crushing the metallic battery case together with the liquid, containing the valuable substance from the inside of the battery case made of the metal,
Screening the contents separated from the separation step and the metal battery case to obtain a recovered material containing the valuable material, and including a valuable step from the lithium ion secondary battery. Collection method of things.   The method for recovering a valuable material from a lithium ion secondary battery according to claim 1, wherein the valuable material is cobalt. The method for recovering a valuable material from a lithium ion secondary battery according to claim 1, wherein the separation step is performed by a wet ball mill that does not use media .   The method for recovering valuable materials from a lithium ion secondary battery according to any one of claims 1 to 3, wherein the amount of liquid used in the separation step is 0.5 kg to 100 kg with respect to 1 kg of the roasted product.   The method for recovering valuable materials from a lithium ion secondary battery according to any one of claims 1 to 4, wherein the sorting step is performed by sieving.   The method for recovering a valuable material from a lithium ion secondary battery according to claim 5, wherein the particle size of the recovered material obtained by sieving is 1 mm or less. A recovered material obtained by the method for recovering a valuable material from a lithium ion secondary battery according to any one of claims 1 to 6, wherein the mixing ratio of iron constituting the metal battery case is 7% or less. Collected material containing valuables characterized by